Continuous pumping unit



S. A. W. OKELL ET AL CONTINUOUS PUMPiNG UNIT Sept; 21, 1937.

Filed June 19, 1956. 3 Sheets-Sheet l S. A. w. OKELL ET AL CONTINUOUSPUMPING UNIT Sept'. 21, 1937.

3 sheets-sheet 2 Filed June 19, 1936 N NV. ww mv nV 5 YH. J fi WW A w 4Q mv A m Q MN g NN w mm RN mm b u W R Nw R m ma aw I ENTORS ATTORNEY$Sept. 21, 1937. s. A. w. OK'ELL ET L CONTINUOUS PUMPING UNIT Filed June19, 1936 5 Sheets-Sheet 3 323 wit; an; M 2&5

GQIIZIX' E TQRS W BY M W ATTCRNEYS zwmo w Nat mw Y W W Patented Sept.21, 1937 iJNi'iZE Di STATES attain PATENT @i'F h-i QB CONTINUOUS PUMPINGUNIT Application June 19, 1936, Serial No. 86,090

20 Claims.

Our present invention relates to pumping mechanisms and aimsto-provide adevice of the general character indicated, which is simple inconstruction, easyand economical to fabricate and assemble, and adaptedto deliver a continuous discharge.

In the accompanying specification we shall describe, and in the annexeddrawings show, an illustrative embodiment of the pumping mechalO nism ofthe present invention. It is, however, to be kept in mind that We do notwish to be limited to the exact details herein described and shown forpurposes of illustration only, inasmuch as changesmay be made in thedetails of construction without the exercise of the inventive faculties,and within the scope of the claims hereto appended.

Before describing our invention in detail, we deem it advisable,briefly, to referto the prior art in the field to which the presentinvention befindsparticular use in connection with the refining ofsugar. In such operations, sugar liquor in a supply tank has thoroughlymixed therein a decolorizing medium, such as a highly activatedvegetable carbon. The mixture of liquor and carbon is generally pumpedto a filtering device containing a plurality of filter leaves, and theliquor passes through these leaves, which are of fine mesh, thecarbonbecoming deposited upon the leaves in the form of acake, and absorbingthe impurities from the liquor as the latter passes therethrough. It hasbeen necessary in the past to use either a pneumatic ejector or acentrifugal pump for delivering the liquor and carbon suspended thereinfrom the supply tankto the filtering device. The pneumatic ejectoroperates in a discontinuous manner; that is, after it has delivered acertain quantity of liquor, its operation ceases while it is beingrefilled and it does not again pump liquor until it has become filled.During the refilling operation, there is a drop in the pressure in theline between the pump and the filtering device, and this results in thecarbon cake dropping off the filter leaves. The disadvantages of suchoperations are believed to be obvious, and require no further discussionhere.

The use of centrifugal pumps presents other disadvantages. For onething, it is difiicult to use pumps of this character in connection withvegetablecar'bon suspensions for the reason that a the pump impellersdue to the high velocity of the metallic moving parts against the liquidcontaining the suspension For another thing violent mechanicalagitation,such as is obtained by using centrifugal pumpsbreaks down thefiocs 5 of the suspension which causes-a condition of dispersion v ordeflocculation, thus preventing the attainment of a high filtrationrate.

These disadvantages are eliminated by means of the pumping mechanism ,ofthe present inven- "10 tion, by means of which we obtain an even; con?tinuous flow. Other advantages of the present invention willbecomeobvious to those skilled in the art to which'thepresent. inventionrelates E as the detailed description thereof progresses. 15

In the accompanyingdrawings:

Fig. l is a top plan view of the pumping mechanism of thepresentinvention;

Fig. 2 is a transverse, sectional view, partly in elevation, taken alongline 2:2 of Fig. l;

Fig. 3 is a similar view taken along line 3-3 of Fig.1;

Fig. 4 is an enlarged, transverse sectional View,

' taken substantially through the center of a valve housingconstituting. part of the present .in- '2 vention;

Fig. 5 is avertical, sectional view, taken along line 55 .of Fig.4;

Fig. 6. isa similar view, taken along line 66 of Fig. 4; 0

Fig. 7 is a schematic view, showing the manner in which the pumpingmechanisms of thepresent inventionare hooked up in apumping system; and.

Fig. .8 is a graphic chart,showing the proper 5 chronological order ofthe operationsof the various parts of .thepumping mechanisms of thepresent invention.

Referring now more in detail, to the aforesaid illustrativeembodiment ofthe pumpingrnecha- 40 nism of the present invention, and with particularreference to Figs. 1 to ,6 inclusive of .the drawings, the letters A andB generally designate, cylindrical tanks of any desired capacityprovided with covers it and, H. The covers are respectively 45 providedwith housings l2 and 53 opening into the tanks through the covers, andadapted to enclose the upper ends of float rods I l-and l5, carrying attheir outer ends floats. A and B. The latter are adapted to rise andfall within the 50 tanks A and B in accordance with the quantity ofliquid therein, and in order to obtain the greatest capacity from thetanks, the covers It) and II thereof are further provided with domes I6and H, which are receptive of the floats A and B 55 when the latter arein their uppermost positions.

The housings l2 and l3 are provided with stuffing boxes I8 and I9, andglands 29 and 2|, and journalled in the stuffing box l8, extendingwithin the housing l2 where it is afiixed to the upper end of the floatrod I4, is a shaft 22, and journalled in the stuiiing box 2| to extendwithin the housing l3 where it is affixed to the upper end of the floatrod I5, is a shaft 23. The outer end of the shaft 22 is journalled in abearing 24, and the outer end of the shaft 23 is journalled in a bearing25.

Fixed upon the shaft 22 intermediate the gland 2|] and bearing 24, arecranks 25 and 21, and fixed upon the shaft 23 intermediate the gland 2iand bearing 25 are cranks 23 and 29. The cranks 29, 21, 28 and 29 arerespectively pivotally connected with connecting rods 39, 3|, 32, and33, each of which has its outer end upturned to support a sliding collardesignated in the drawings at 34, 35, 36 and 31.

Communicating with the interior of the tanks A and B through the covers3 and H adjacent the domes l6 and H, are pipes 38 and 39, which pipesare adapted to support valve blocks 49 and 4|, and at the same timecommunicate with a manifold 42 with which each of the blocks isprovided. Inasmuch as each of the valve blocks 49 and 4| are similarinconstruction, only one of the same will be described in detail,reference being had particularly to Figs. 4, 5 and 6 of the drawings.

The manifold 42 communicates with vertical passages 43 and 44, theformer communicating with an air vent 45, and the latter communicatingwith an air inlet 49. Traversing the vertical passages 43 and 44, arehorizontal openings 41, and each of the openings 4'! is adapted to housea piston valve, four of which are shown in the drawings, designated at48, 49, 59 and 5|. The valve 48 is the vent valve of the tank A and thevalve 49 is the air inlet valve of the same tank while the valve 59 isthe air inlet valve of the tank B and the valve 5| is the vent valve ofthe same tank.

Each of the valves 48, 49, 59 and 5| is provided with an annular groove52, adapted, when the valves are operated within the blocks 49 and 4|,to register with the vertical passages 43 and 44, thus opening orclosing the communications between the atmosphere and the interior ofthe particular tank or the source of compressed air and the interior ofthe particular tank.

Before describing the details of the mechanism of the present inventionany further, it is thought that a better understanding of the comingdescription will be had if at this point the manner of hooking up thepumping mechanism of the present invention is referred to.

In Fig. 7 of the drawings, there is shown an inlet pipe 53, whichcommunicates with a source of supply of liquor, and which leads to amanifold 54, provided with a check valve 55 for the tank A and 55 forthe tank B. Beyond each check valve, the manifold communicates with thetanks A and B. The tanks are provided with an outlet manifold 51including check valves 58 and 59, beyond which the manifold communicateswith a discharge pipe 69. A source of compressed air, such as thecompressor 6| communicates through the pipe 62 with a manifold 93, whichbranches off so as to communicate with the passages 46 of each of thevalve blocks 49 and 4|, the passage 45 of each of such blockscommunicating merely with the atmosphere.

Resuming the detailed description of the mechanisms of the presentinvention, each of the valves 48, 49, 59 and 5| is provided with acentral longitudinal opening 64 adapted to receive valve operating rods55, 99, El and 68, and respectively slidable on each of these rods arethe sliding collars 34, 36, 35 and 37.

Upon the outer end of each of the rods 55, 6'0, 5'! and 68, there isfixed a collar 59, the purpose of which, as will be more fullyunderstood from the description of the operation of the presentinvention, is to operate the valves 49, 49, 59 and 5| in one direction.Fixed upon the rod 95, with the sliding collar 34 intermediate the same,is a pair of collars T9 and 1|. Fixed upon the rod 66 with the slidingcollar 36 intermediate the same, is a pair of collars l2 and 13. Fixedupon the rod 6'! with the sliding collar 35 intermediate the same, is apair of collars l4 and I5; and fixed upon the rod 68 with the slidingcollar 3'! intermediate the same, is a pair of collars l6 and H.

Inasmuch as it is necessary that the pumping mechanisms of the presentinvention function smoothly and continuously, it is desirable that thevalves 49, 49, 59 and 5| operate with a snap action. For this purpose,we provide each of such valves with a toggle arrangement 78. Inasmuch asall of the toggle arrangements are the same, we shall describe only one.Affixed to the upper and lower surfaces of the valve blocks 45 and 4|,adjacent each valve, are flat springs 79 and 89, the inner ends of whichare bent, as at 9|, to support toggle members 92 and 33. The inner endsof the latter engage a grooved collar 94 fixed upon the correspondingvalve operating rod. By means of such arrangement, as the valveoperating rods 65, 69, 51 and 98, are moved in either direction, thetoggle members 92 and 83 are moved toward their vertical positions andthe slightest movement beyond such vertical position-s, known as deadcenter, causes the springs l9 and to move the valve operating rods witha snap action in the same direction. This in turn operates thecorresponding valve.

In order that the discharge from the tanks A and B be continuous, it isnecessary that the floats A and B of the tanks A and B operate the airvalves 49 and 59 to close the same, but, the opening of said valves mustbe performed by the opposite tanks; that is, the opening of the valve 49must be performed by the float B of the tank B and the opening of thevalve 59 must be performed by the fioat A of the tank A. In order tcarry this out, there is afiixed to the collars l9 and i5 arms 85 and96, the outer ends of these arms being provided with openings largerthan the diameter of the rods 66 and ti, so that they may freely slidealong the same.

This completes the description of the mechanics of the pumping mechanismof the present invention, and the structural operation thereof is asfollows:

Assuming that the tank A is almost full of liquor and is in the .act ofdischarging the same, at such time the float A will be descending, andthe shaft 22 to which. such float is attached, will be rotating, so thatthe crank 29 will push the connecting rod 39. This motion causes thesliding collar 34 to move along the rod 95 so that it impinges upon thearm 95 fixed to the collar l9. As the float A continues to descend, thevent valve actuating rod 55 is pushed through the piston valve 48, andthe outer end of the arm 85 slides upon the valve operating rod 69, andimpinges upon the fixed collar #2.

Thus both col- 4 the toggles l8 of the valves 58 and 39 reach their deadcenter positions. At thisinstant, the toggles trip and causethe collarsit] and T2 to be moved forwardly with a snap action to actuate i thevalves 58. and' iaopening the former and closing the latter. As the airescapes from the tank A through the pipe 38, manifold 42 and openings[13 and t5, the pressure within such tank drops and a fresh charge ofliquor from the source of supply passes through the pipe. 53, manifold5t, past the check valve 55 and into the tank A. As the fresh chargeenters the tank A, the fioatA rises. As the float A rises, the crank 2'5pulls the sliding collar 34 backwardly until it impinges upon the fixedcollar ll. This causes the. vent valve operating rod 65 to be movedbackwardly until, when the tank is full, the toggle E8 of thisparticular (valve trips again in the opposite direction, andcloses thevent valve it. However, as

the collar ill moves backwardly' under the action of the rising float A,the arm 85' backs away from the fixed collar l2, thus leaving the airinlet valve 439 of the tank A in its closed position. It will,therefore, be seen thatwhile the arm 85 acts to close the air inletvalve 29', it does not open this valve.

, The opening of the air valve id on the tank A is effected by theactionof the float B of the tank B. When the tankB is on its pumping strokeand the float B is descending, the crank 28 on the shaft 23, which isoperated by the fioat B, pulls the connecting rod 32 which causes thesliding collar 3% to move along the rod 6% to pullthe fixed collar #3,thus causing the valve operating rod tit to be moved in the. directionof the tank B. At a predetermined time,.this movement causes the toggleE8 of the valve A9. to reach its dead center position after which ittrips, and causes the valve tt'to open. Inasmuch as both tanks A and Bare constructed exactly the same, and are connected with each otherthrough theirrespective valve mechanisms in exactlythe same manner, thecycle? of operations just described, is exactly the same for the valves50 and 5! of the tank B. V

This completes the description of the operation of the mechanics of thepumping mechanism of the present invention, but it is thought that amore thorough understanding of the same will be had by referring to thegraphic chart shown in Fig. 8' of the drawings.

In this figure, the center of the shaft 22 of the float A of the tank Ais designatedby the reference character 883, and the are through whichthe center 9} of the float A travelsis also indicated. On the right ofthis view, the. center of the shaft 23 which carries the fioat B of thetank B is indicated at 92 and the arc through which the center t t ofthe float B travels is also indicated. The illustration at the top ofthis View indicates the operation. of the valves 5! and 5% of the tank Band the illustration at the bottom of this view indicates the operationof the valves A9 and A8 of the tank A. In the central illustration ofthis View intermediate the arcs of the floats A and'BK-it is indicatedthe height of the liquid in either or both of the tanks, at any instant,the time units being plotted'as abscissae,

and the depths of the liquid in the tanks as ordinates; The full lineindicates the depth of the liquid in the tank A and the broken lineindicates the corresponding depth in the tank B.

Starting from the left of this illustration, it is to be noted that bothtanks are pumping until the points 9A and 98.

the. pointof time indicated by the reference charthe rate at which itwas pumping, as indicated by thesteeper slope of the graph between thepoint-s95 and 9%. The tangent of the angle made by the line betweenthepoints 95 and 96 with the horizontal is exactly twice the tangentjof theangle: made by the; line between the point 91, which'was the start ofthe pumping stroke of the tank B; and point 95 which was the point atwhich time the tank A stopped pumping. t is to be noted that the tank Areaches the top of its filling stroke at the point98, and the rate offilling is considerably greater than the rate of pumping as indicated bythe slope of the graph between This is easily arranged by making theintake pipes to the pumps of larger bore than the discharge pipes.

When the point 98 is reached it will be noted that the tank B is stillpumping alone, and that the. tank A remains stationary in a filledposition, as indicated by the graph, between thepoints 98 and 953.. Byadjusting the fixed collars on the valve rods, it is possible to arrangethe operation of the pumping mechanism of the present invention so thateither of the tanks will open the air valve of the other tank and startthe pumping at any desired point toward the end of the stroke of thetank which is approaching the end of its stroke at that time. Thus whenthe tank B reaches the point 96, substantially less than A; of'itsstroke from the lower limit, .the air valve of the tank A is opened withthe result that tank A starts pumping from the point (i9 and continuesuntil the point llltis reached, at which time the tank B has reached thepoint ml corresponding to the. end of its pumping stroke. From the pointM .tothe point Hit the tank A is pumping at half its normal rate, andcorrespondingly from the point 9% to the point lll'l the tank B ispumping at half its normal rate. However, at the point lili t'he'tank Bfinishes pumping and starts to fill so that from the point 188 on thetank A pumps at double its rate.

These cycles are repeated'and it will be understood thatinasmuch as atleast one tank is alof the tank B and the illustration of the operationof the valves of the tank A are projected from the center illustration.In the upper illustration, there is shown two sets of three horizontallines, corresponding respectively to the operation of the vent and airvalves of the tank B, the median line of each setof three linescorresponding to the dead point of the toggle of the particular valve.The outside lines'of each set show respectively the opened and closedpositions of the valve, while the distance between the two outside linescorresponds'to the total travel of the toggle of the particular valve.

The toggle travels for half of its total distance slowly which brings itat the dead point. Thereafter it travels substantiallyinstantane'ouslyfor the remaining half of its distance. This isgraphically represented on the chart, where, for example, at the pointI02, the toggle of the vent valve 55 of the tank B begins to be pushedslowly to its dead point indicated at I03. At this instant, the toggletrips, and the instant opening of the valve Si is effected, as indicatedby the short vertical line intermediate the point Hi3 and the point EM.The time period during which the valve 55 remains open is indicated bythe horizontal line between the point I04 and the point H15, andthereafter the toggle starts to be actuated in the opposite direction asindicated by the sloping line from Hi5 and the point I66. Upon reachingthe point Hit, the toggle snaps past the dead point, and the valve 5|closes, this being indicated by the short vertical line between thepoint I06 and the point Nil. Exactly the same cycle of operations takesplace for the rest of the valves, and hence a detailed description isdeemed unnecessary.

Referring now to the two diagrams showing the arcs through which thefloats A and B travel, it is to be noted that the angular position ofthe lines til-9i or 9293 is determined by projection from the points 94,98, 99, I00, etc. Similarly, from any given angular position of thefloat rods of the. floats A and B, the corresponding depths of liquid inthe particular tank can be ascertained by projecting in the oppositedirection. For example, if it is desired to determine the angularposition of the float A of the tank A at the instant when it begins tomove the toggle for opening the valve 59 of the tank B, it is to benoted that this operation begins at the point 8. The corresponding levelof the center of the float A, is obtained by projecting verticallydownward from the point I98 until the vertical line intersects the graphrepresenting the tank A at the point IE9. Projecting horizontally to theleft from the point H19, we intersect the are which indicates the locusof the center of the float A of the tank A at the point llil. This is,therefore, the point at which the center of the float A of the tank A islocated when it begins to actuate the toggle of the air valve of thetank B. Similarly, by projecting downward from the point I l i, thegraph of the tank A is intersected at the point H2, and projecting fromthis point horizontally, we get the point H3 on the arc of the float A.By joining the points H0 and M3 to the center 90, there is obtained theangle. through which the float rod of the float A moves during the wholeof the operation of the opening of the air valve 50 of the tank B. Byutilizing these various calculations, the size of the cranks andconnecting rods, and the points at which the fixed collars should bepositioned on the valve operating rods can readily be determined.

This completes the description of the aforesaid illustrative embodimentof the present invention, and the operation thereof. It will be notedfrom such description that the pumping mechanisms of the presentinvention are simple in construction, easy and economical to fabricateand assemble, and result in a pumping unit whereby there may be obtainedan even, continuous discharge. Other advantages of the device of thepresent invention will be obvious to those skilled in the art to whichthe present invention relates.

What we claim as our invention is:

l. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks,

and means, associated with each of said tanks and operable by thecharging and discharging thereof, to open and close. the air outlet andonly close the air inlet of its own tank, and open the air inlet of theother tank.

2. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks, means, associated with each ofsaid tanks and operable by the charging thereof, to close the air outletof its own tank, and means, associated with each of said tanks andoperable by the discharging thereof, to only open the air inlet of theother tank and open the air outlet and only close the air inlet of itsown tank.

3. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks, and means, associated with each ofsaid tanks-and operable by the charging and discharging thereof, tosuccessively close the air outlet of one of said tanks, then open theair inlet of the same tank, and thereafter simultaneously open the airoutlet and close the air inlet of the other of said tanks.

4. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks, and means, associated with each ofsaid tanks and operable by the charging and discharging thereof, tosuccessively close the air outlet of one of said tanks at the end of itsown charging stroke, then open the air inlet of the same tank as theother tank nears the end of its discharge, and thereafter simultaneouslyopen the air outlet and close the air inlet of said second tank when thelatter reaches the end of its discharge.

5. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks, and means, associated with each ofsaid tanks and operable by the charging and discharging thereof, to openand close the air outlet and only close the air inlet of its own tank,and open the air inlet of the other tank, each of said means including afloat operable within each of said tanks,

valves controlling said air inlets and outlets and adjustableconnections intermediate said floats and said valves.

6. Pumping mechanism comprising, a pair of tanks charged from a commonsource. of supply I and discharging into a common outlet, an air inletand an air outlet for each of said tanks, means, associated with each ofsaid tanks and operable by the charging thereof, to close the air outletof its own tank, and means, associated with each of said tanks andoperable by the discharging thereof, to only open the air inlet of theother tank and open the air outlet and only close the air inlet of itsown tank, each of said means including a float operable within each ofsaid tanks, valves controlling said air inlets and outlets andadjustable connections intermediate said floats and said valves.

7. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan. air outlet for each of said tanks, and means, associated with eachof said tanks and operable by the charging and discharging thereof, tosuccessively close the air outlet of one outlet and close the air inletof the other of said tanks, each of said means including a floatoperable within each of said tanks, valves controlling said air inletsand outlets and adjustable connections intermediate said floats and saidvalves.

8. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet/andan air outlet for each of said tanks, and means, associated with each ofsaid tanks and operable by the charging and discharging thereof, tosuccessively close the air outlet of one of said tanks at the end of itsown charging stroke, then open the air inlet of the same tank as theother tank nears the end of its discharge, and thereafter simultaneouslyopen the air outlet and close the-air inlet of said second named tankwhen the latter reaches theend of its discharge, each of said meansincluding a float operable within each of said tanks, valves controllingsaid air inlets and outlets and adjustand discharging into a commonoutlet, an air "inlet and an air outlet for each of said tanks,

and means, associated with each of said tanks and-operable by thecharging and discharging thereof, to'open and close the air outlet and.only close the air inlet of its own tank, and open the 'air inlet of theother tank, each of said means including a float operable within each ofsaid tanks, valves controlling said air inlets and outlets, valveoperating rods associated with said valves, a plurality of collars fixedupon said rods at predetermined points, and connections intermediatesaid floats and said rods, operable by said floats, slidable along thelength of said rods andcooperable with said collars to actuate saidvalves. 7

.10. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply anddischarging into a common outlet, an air inlet andan air outlet for each of said tanks, means, associated with each ofsaid-tanks and operable by the charging thereof, to close the air outletof its own tank, and means, associated with each of said tanks andoperable by the discharging thereof, to only open the air inlet of theother tank and open the air outlet and only close the air inlet of itsown tank, each of said means including a float operable within each ofsaid tanks, valves controlling said air inlets and outlets,valveoperating rods associated with said valves, a plurality of collarsfixed upon said rods at predetermined points, and connectionsintermediate said floats and said rods, operable by said floats,slidable along the length of said rods and cooperable with said collarsto actuate said valves.

11. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks, and means, associated with each ofsaid tanks and operable by the charging and discharging thereof, tosuccessively close the air outlet of one of said tanks, then open theair inlet of the same tank, and thereafter simultaneously open the airoutlet and close the air inlet of the other of said tanks, each of saidmeans including a float operable within each of said tanks, valvescontrolling said air inlets and outlets, valve operating rods associatedwith said valves, a plurality of collars fixed upon said rods atpredetermined points, and connections intermediate said floats and saidrods, operable by said floats, slidable along the length of said rodsand cooperable with said collars to actuate said valves. v

12. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply means, associated with each of said tanks and operableby the charging and discharging thereof, to successively-close the airoutlet of oneof said tanks at the end of its own charging stroke, thenopen the-air inlet of the same tank as the other tank nears the end ofits discharge, and thereafter simultaneously open the air outlet andclose the air inlet of said second named tank when the latter reachesthe end of its discharge, each of said means including a float operablewithin each of said tanks, valves controlling said air inlets andoutlets, valve operating rods associated with said valves, a pluralityof collars fixed upon said rods at predetermined points, and connectionsintermediate said floats and said rods, op-

erable by said floats, slidable along the length of said rods andcooperable with said collars to actuate said valves.

13. In a device of the class described, a tank having a liquor inlet anda liquor outlet, an air inlet for receiving compressed air to theinterior of said tank to eject the liquor therefrom, an air outlet forventing the compressed air to the atmosphere to permit refilling of saidtank, valves controlling said air inlet and air outlet, and means,operated by the rise and fall of the liquor in said tank, for openingand closing said air outlet valve, but only closing said air inletvalve, in combination with means operatively coupled with saidfirst-named means for opening said air inlet valve.

14. In a device of the class described, a tank having a liquor inlet anda liquor outlet, an air inlet for receiving compressed air to theinterior of said tank to eject the liquor therefrom, an air outlet forventing the compressed air to the atmosphere to permit refilling of saidtank, valves controlling said air inlet and air outlet, and means,operated by the rise and fall of the liquor in said tank, for openingand closing said air outlet valve, but only closing said air inletvalve, said means including a float operable within said tank, avalve-actuating rod associated with each of said valves, a plurality ofcollars fixed on said rods at predetermined points, connectionsintermediate said floats and said collars, and means, secured to one ofthe collars carried by the rod of said air outlet valve, engageable withone of the collars carried by the rod of said air inlet valve when therod of said air outlet valve moves toward said valves open positiononly, in combination with means operatively c0upled with saidfirst-named means for opening said air inlet valve.

15. In a device of the class described, a tank having a liquor inlet anda liquor outlet, an air inlet for receiving compressed air to theinterior of said tank to eject the liquor therefrom, an air outlet forventing the compressed air to the atmosphere to permit refilling of saidtank, valves controlling said air inlet and air outlet, and means,operated by the rise and fall of the liquor in said tank, for openingand closing said air outlet valve, but only closing said air inletvalve, said means including a float operable Within said tank, avalve-actuating rod associated with each of said valves, a plurality ofcollars fixed on said rods at predetermined points, connectionsintermediate said floats and said collars, and an arm,

secured to one of the collars carried by the rod of said air outletvalve, having an opening at its outer end to permit its sliding alongthe length of the rod of said air inlet valve, engageable with one ofthe collars carried by the rod of said air inlet valve when the rod ofsaid air outlet valve moves toward said valves open position only, incombination with means operatively coupled with said first-named meansfor opening said air inlet valve.

16. Pumping mechanism comprising, a pair of tanks charged-from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks, and means, associated with each ofsaid tanks and operable by the charging and discharging thereof, to openand close the air outlet and only close the air inlet of its own tank,and open the air inlet of the other tank, each of said means including afloat operable Within each of said tanks, valves controlling said airinlets and outlets and adjustable connections intermediate said floatsand said valves, said floats, valves and adjustable connections beingoppositely disposed.

1'7. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks, means, associated with each ofsaid tanks and operable by the charging thereof, to close the air outletof its own tank, and means, associated with each of said tanks andoperable by the discharging thereof, to only open the air inlet of theother tank and open the air outlet and only close the air inlet of itsown tank, each of said means including a float operable within each ofsaid tanks, valves controlling said air inlets and outlets andadjustable connections intermediate said floats and said valves, saidfloats, valves and adjustable connections being oppositely disposed.

18. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks, and means, associated with each ofsaid tanks and operable by the charging and discharging there-'- of, tosuccessively close the air outlet of one of said tanks, then open theair inlet of the same tank, and thereafter simultaneously open the airoutlet and close the air inlet of the other of said tanks, each of saidmeans including a float 0perable within each of said tanks, valvescontrolling said air inlets and outlets and adjustable connectionsintermediate said floats and said valves, said floats, valves andadjustable connections being oppositely disposed.

19. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks, and means, associated with each ofsaid tanks and operable by the charging and discharging thereof, tosuccessively close the air outlet of one of said tanks at the end of itsown charging stroke, then open the air inlet of the same tank as theother tank nears the end of its discharge, and thereafter simultaneouslyopen the air outlet and close the air inlet of said second named tankwhen the latter reaches the end of its discharge, each of said meansincluding a float operable within each of said tanks, valves controllingsaid air inlets and outlets and adjustable connections intermediate saidfloats and said valves, said floats, valves and adjustable connectionsbeing oppositely disposed.

20. Pumping mechanism comprising, a pair of tanks charged from a commonsource of supply and discharging into a common outlet, an air inlet andan air outlet for each of said tanks, and means, associated with each ofsaid tanks and operable by the charging and discharging thereof, to openand close the air outlet and only close the air inlet of its own tank,and open the air inlet of the other tank, each of said means including afloat operable Within each of said tanks, valves controlling said airinlets and outlets, valve operating rods associated with said valves, aplurality of collars fixed upon said rods at predetermined points, andconnections intermediate said floats and said rods, operable by saidfloats, slidable along the length of said rods and cooperable with saidcollars to actuate said valves, said floats, valves, collars andconnections being oppositely disposed.

STANLEY A. W. OKELL.

WALTER F. DEMMERLE.

